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Related papers: Chromatic quasisymmetric functions

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We propose a conjectural counting formula for the coefficients of the chromatic symmetric function of unit interval graphs using reinforcement learning. The formula counts specific disjoint cycle-tuples in the graphs, referred to as…

Combinatorics · Mathematics 2024-10-28 Gergely Bérczi , Jonas Klüver

Cylindric skew Schur functions, which are a generalisation of skew Schur functions, arise naturally in the study of P-partitions. Also, recent work of A. Postnikov shows they have a strong connection with a problem of considerable current…

Combinatorics · Mathematics 2007-05-23 Peter McNamara

Recently a new basis for the Hopf algebra of quasisymmetric functions $QSym$, called quasisymmetric Schur functions, has been introduced by Haglund, Luoto, Mason, van Willigenburg. In this paper we extend the definition of quasisymmetric…

Combinatorics · Mathematics 2012-07-24 Christine Bessenrodt , Kurt Luoto , Stephanie van Willigenburg

It is well known that the $q$-Whittaker polynomials, which are $t=0$ specializations of the Macdonald polynomials $P_\lambda(X;q,t)$, expand positively as the sum of Schur polynomials. Macdonald polynomials have a quasisymmetric refinement:…

Combinatorics · Mathematics 2026-01-09 Olya Mandelshtam , Harper Niergarth , Kartik Singh

We make a broad conjecture about the $k$-Schur positivity of Catalan functions, symmetric functions which generalize the (parabolic) Hall-Littlewood polynomials. We resolve the conjecture with positive combinatorial formulas in cases which…

Combinatorics · Mathematics 2018-11-07 Jonah Blasiak , Jennifer Morse , Anna Pun , Daniel Summers

In this article we show how to compute the chromatic quasisymmetric function of indifference graphs from the modular law introduced by Guay-Paquet. We provide an algorithm which works for any function that satisfies this law, such as…

Combinatorics · Mathematics 2020-06-23 Alex Abreu , Antonio Nigro

The Stanley-Stembridge conjecture associates a symmetric function to each natural unit interval order $\mathcal P$. In this paper, we define relations \`a la Knuth on the symmetric group for each $\mathcal P$ and conjecture that the…

Combinatorics · Mathematics 2020-05-15 Dongkwan Kim , Pavlo Pylyavskyy

For the renormalised sums of the random $\pm 1$-colouring of the connected components of $\mathbb Z$ generated by the coalescing renewal processes in the "power law P\'olya's urn" of Hammond and Sheffield we prove functional convergence…

Probability · Mathematics 2023-01-18 Jan Lukas Igelbrink , Anton Wakolbinger

We describe a combinatorial formula for the coefficients when the dual immaculate quasisymmetric functions are decomposed into Young quasisymmetric Schur functions. We prove this using an analogue of Schensted insertion. Using this result,…

Combinatorics · Mathematics 2016-06-14 Edward E. Allen , Joshua Hallam , Sarah K. Mason

We obtain the Schur positivity of spider graphs of the forms $S(a,2,1)$ and $S(a,4,1)$, which are considered to have the simpliest structures for which the Schur positivity was unknown. The proof outline has four steps. First, we find…

Combinatorics · Mathematics 2023-05-16 Jean-Yves Thibon , David G. L. Wang

Determining whether two graphs are isomorphic is an important and difficult problem in graph theory. One way to make progress towards this problem is by finding and studying graph invariants that distinguish large classes of graphs. Stanley…

Combinatorics · Mathematics 2020-10-22 Jeremy Zhou

The solution of Shareshian-Wachs conjecture by Brosnan-Chow linked together the cohomology of regular semisimple Hessenberg varieties and graded chromatic symmetric functions on unit interval graphs. On the other hand, it is known that…

Combinatorics · Mathematics 2022-06-01 Mikiya Masuda , Takashi Sato

The chromatic symmetric function (CSF) of Dyck paths of Stanley and its Shareshian-Wachs $q$-analogue have important connections to Hessenberg varieties, diagonal harmonics, and LLT polynomials. In the case of, so-called, abelian Dyck paths…

Combinatorics · Mathematics 2021-04-22 Laura Colmenarejo , Alejandro H. Morales , Greta Panova

Stanley's theory of $(P,\omega)$-partitions is a standard tool in combinatorics. It can be extended to allow for the presence of a restriction, that is a given maximal value for partitions at each vertex of the poset, as was shown by Assaf…

Combinatorics · Mathematics 2023-03-17 Philippe Nadeau , Vasu Tewari

Motivated by classical problems in extremal graph theory, we study a chromatic analogue of Roth-type questions for linear equations over $\mathbb F_p$. Given a homogeneous equation $\mathcal L:\sum_{i=1}^k c_i x_i=0$ with $k\ge 3$, we study…

Combinatorics · Mathematics 2026-03-06 Hong Liu , Zhuo Wu , Ningyuan Yang , Shengtong Zhang

We generalize several classical results about Schur functions to the family of cylindric Schur functions. First, we give a combinatorial proof of a Murnaghan--Nakayama formula for expanding cylindric Schur functions in the power-sum basis.…

Combinatorics · Mathematics 2023-11-14 Per Alexandersson , Ezgi Kantarci Oğuz

We introduce the quasi-key basis of the polynomial ring. We prove this basis contains the quasi-Schur polynomials of of Haglund, Luoto, Mason and van Willigenburg and that stable limits of quasi-key polynomials are quasi-Schur functions,…

Combinatorics · Mathematics 2020-03-05 Sami Assaf , Dominic Searles

We make a systematic study of a new combinatorial construction called a dual equivalence graph. We axiomatize these graphs and prove that their generating functions are symmetric and Schur positive. This provides a universal method for…

Combinatorics · Mathematics 2020-03-05 Sami H. Assaf

We establish Guay-Paquet's unpublished linear relation between certain chromatic symmetric functions by relating his algebra on paths to the $q$-Klyachko algebra. The coefficients in this relations are $q$-hit polynomials, and they come up…

Combinatorics · Mathematics 2022-08-09 Philippe Nadeau , Vasu Tewari

We develop a general theory of higher semiadditive Fourier transforms that includes both the classical discrete Fourier transform for finite abelian groups at height $n=0$, as well as a certain duality for the $E_n$-(co)homology of…

Algebraic Topology · Mathematics 2022-11-29 Tobias Barthel , Shachar Carmeli , Tomer M. Schlank , Lior Yanovski